Unsaturated expansive soil fissure characteristics combined with engineering behaviors  

作　　者：李雄威 王勇 俞竞伟 王艳丽 

机构地区：[1]School of Civil Engineering&Architecture(Changzhou Key Lab of Structure Engineering and Material Properties),Changzhou Institute of Technology [2]State Key Laboratory of Geomechanics and Geotechnical Engineering(Institute of Rock and Soil Mechanics,Chinese Academy of Sciences) [3]Key Laboratory of Geotechnical Mechanics and Engineering of Ministry of Water Resources(Yangtze River Scientific Research Institute)

出　　处：《Journal of Central South University》2012年第12期3564-3571,共8页中南大学学报（英文版）

基　　金：Projects(41102229,51109208)supported by the National Natural Science Foundation of China;Project(2011CDB407)supported by Natural Science Foundation of Hubei Province,China;Project supported by Qing Lan Project of Jiangsu Province,China

摘　　要：The relationship among the surface fissure ratio, moisture content, seepage coefficient and deformation modulus of field unsaturated expansive soil in Nanning, Guangxi Province, China, was obtained by a direct or indirect method. Digital images of expansive soil of the surface fissure with different moisture contents were analyzed with the binarization statistic method. In addition, the fissure fractal dimension was computed with a self-compiled program. Combined with in situ seepage and loading plate tests, the relationship among the surface fissure ratio, moisture content, seepage coefficient and deformation modulus was initially established. The surface fissure ratio and moisture content show a linear relation, ＂y=-0.019 1x＋1.028 5＂ for rufous expansive soil and ＂y=-0.07 1x＋2.610 5＂ for grey expansive soil. Soil initial seepage coefficient and surface fissure ratio show a power function relation, ＂y=1× 10^-9exp（15.472x）＂ for rufous expansive soil and ＂y=5× 10^-7exp（4.209 6x）＂ for grey expansive soil. Grey expansive soil deformation modulus and surface fissure ratio show a power fimction relation of ＂y=3.935 7exp（0.993 6x）＂. Based on the binarization and fractal dimension methods, the results show that the surface fissure statistics can depict the fissure distribution in the view of two dimensions. And the evolvement behaviors of permeability and the deformation modulus can indirectly describe the developing state of the fissure. The analysis reflects that the engineering behaviors of unsaturated expansive soil are objectively influenced by fissure.The relationship among the surface fissure ratio,moisture content,seepage coefficient and deformation modulus of field unsaturated expansive soil in Nanning,Guangxi Province,China,was obtained by a direct or indirect method.Digital images of expansive soil of the surface fissure with different moisture contents were analyzed with the binarization statistic method.In addition,the fissure fractal dimension was computed with a self-compiled program.Combined with in situ seepage and loading plate tests,the relationship among the surface fissure ratio,moisture content,seepage coefficient and deformation modulus was initially established.The surface fissure ratio and moisture content show a linear relation,"y=0.019 1x+1.028 5" for rufous expansive soil and "y=0.071x+2.610 5" for grey expansive soil.Soil initial seepage coefficient and surface fissure ratio show a power function relation,"y=1×10-9 exp(15.472x)" for rufous expansive soil and "y=5×10-7 exp(4.209 6x)" for grey expansive soil.Grey expansive soil deformation modulus and surface fissure ratio show a power function relation of "y=3.935 7exp(0.993 6x)".Based on the binarization and fractal dimension methods,the results show that the surface fissure statistics can depict the fissure distribution in the view of two dimensions.And the evolvement behaviors of permeability and the deformation modulus can indirectly describe the developing state of the fissure.The analysis reflects that the engineering behaviors of unsaturated expansive soil are objectively influenced by fissure.

关 键 词：expansive soil surface fissure ratio fractal dimension PERMEABILITY deformation modulus 

分 类 号：TU411.3[建筑科学—岩土工程]